BCHS 3304 1st EditionExam # 1 Study Guide Lectures: 1 – 7- Miller Urey experiments: origin of life o At the end of one week, two percent of the carbon had formed amino acids that are used to make proteins in living cells, with glycine as the most abundant. Sugars, lipids, and some of the building blocks for nucleic acids were also formed.o These experiments demonstrate that essential compounds to life can be made under early earth conditions. - Evolutiono Simple inorganic /organic molecule generate biomoleculeo Simple biomolecule generate complicated biomoleculeo Evolution is not directed towards a particular goalo Evolution requires variations and reproductiono Evolution is constrained by its past.o Evolution is ongoing.- Living organisms are composed of lifeless molecules- Physical Units of Space, Time, and Energy.o C - C bond is 1.54 Å 1 mm = 10-3 mo Hemoglobin 65Å 1 mm = 10-6 mo Ribosomes 300Å 1 nm = 10-9 mo Viruses 100 - 1000Åo Cells 7 mm or 7 x 104 Åo 1 Å 10 Å 100 Å 1000 Å 104 Å 105 Å o 10-10 m 10-9 m 10-8 m 10-7 m 10-6 m 10-5 mo Limit of a light microscope = 2000 Å or 0.2mmo 1 Å Þ 104 Å knowledge comes from X-ray crystallography, electron microscope or atomic force microscope- Free Energy and Free Energy Changeo If DG < 0 (negative), a process is spontaneous.o If DG > 0 (positive), a process is nonspontaneous.o If DG = 0, neither the forward nor the reverse process is favored; there is no net change, and the process is at equilibrium.- First Law: DU = Ufinal - Uinitial = q - wo +q means system gains heat Endothermico -q means system releases heat Exothermico +w means system done work on surroundingo -w means surrounding done work on system o The q and w may vary from process to process, but as long as the initial and the final states are the same, DU will be the same.o U : a state function dependent on the current properties only.- Now if we are at equilibrium or DG = 0Thenobadco[B][A][D][C]RTln G 0G DDobadco[B][A][D][C]RTln G DoeqoRTlnKG D- Osmosis and diffusionoo- Life organisms are open systems at steady states but not at equilibrium- Optical activity - The ability to rotate plane - polarized lighto Asymmetric carbon atomo Chirality - Not superimposableo Mirror image – enantiomerso (+) dextrorotatory - right - clockwiseo (-) Levorotatory - left counterclockwise- Dissociation of H2Oo OHHOH2o Water also dissociates [H2O] = 55.5oKw=[H+][OH-]=10- 14o Ionization constant for watero pH = -log([H+])- Henderson - Hasselbalch equationo From ][]][[HAAHKo Rearrange ][][][AHAKHo Take (-)Log of each ][][loglogHAAKpHo][][logHAApKpH- Characteristics of Amino Acidso There are three main physical categories to describe amino acids:1) Non polar “hydrophobic” nine in all- Glycine, Alanine, Valine, Leucine, Isoleucine, Methionine, Proline, Phenylalanine and Tryptophan2) Uncharged polar, six in all - Serine, Threonine, Asparagine, Glutamine Tyrosine, Cysteine 3) Charged polar, five in all- Lysine, Arginine, Glutamic acid, Aspartic acid, and Histidine - Acid - Base properties of amino acidso[HA]][Alog pK pH-o Isoelectric point (pI): the pH where a protein carries no net electrical chargeo pI = ½(pKi +
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